MX-5500...YELLOW IS MISSING

[dacjkhadley]

Not all the time, but the client was saying that the color was not right on prints and copies. Performed sim 64-1 and changed a to 11 to print out all four colors and the very first one came out fine. So I went back to copy mode and tried to copy a very colorful original and yellow was missing. Went back to 64-1 and tried again and yellow was missing. I tried swapping the magenta and yellow drum units and it stayed with yellow. Placed a piece of tape over the grid and tried to make a skyshot using just 1 color and got a blank sheet of paper. Stopped the process in mid stream and had a solid band on the drum, so charge is indeed working. Swapped the LSU with one from a returned machine and same issue. Swapped PCU, MFP and MFP mother board and still getting the same thing. The MFP was Sharp's idea. The only thing I haven't mentioned is if you cycle the power, yellow will come back for 1 set or 1 copy, but as soon as you try a second set or copy, it is gone again.

Anyone see anything like this before?

[mrfixit]

Re: MX-5500...YELLOW IS MISSING

Try swapping the transfer belt unit, might be that the yellow transfer roller isn't engaging all the way.

[mansart]

Re: MX-5500...YELLOW IS MISSING

Take out the yellow LSU shutter and try.

Parts guide Sec 37 item 5

[dacjkhadley]

Re: MX-5500...YELLOW IS MISSING

Forgot to mention, already remove the yellow shutter, thought about it being warped, not the case. Also, when the tape was on the charger and had the solid band on the drum, it did transfer to the belt. Is it possible I have a HVT that is being intermittent for yellow?

[rainmaker]

Re: MX-5500...YELLOW IS MISSING

its sounds like the yellow shutter is not opening.there is a solenoid that opens the shutter,it could be sticking,might have toner in the back,take the yellow drum and dv unit out and in the rear you will see the solenoid. check it and the rail that it is attached...good luck

[chris_c]

Re: MX-5500...YELLOW IS MISSING

I'm actually having the same problem on a mx6200. The machine was in storage, unused for 2 years. When we moved it to its new location, it worked ok, but had some quality issues that needed to be fixed before we would put it under maintenance. Did a full pm and started have the issue. Yellow works fine for 50 copies, then disappears after second run. I've double checked and switched out the mc unit. Have you found a repair for it yet?

[draph]

Re: MX-5500...YELLOW IS MISSING

Have you tried a developing unit? I've seen this problem many times over the years when the shaft on the back of the mag roller was coming loose. First time it drove me up the wall until it finally broke off
completely.

draph

[divad2k1]

Re: MX-5500...YELLOW IS MISSING

Replace the unit that drive the transfert belt cam.

Similar problem in mx35-45 was caused by a damaged shaft and bushing in the main drive unit.

[chris_c]

Re: MX-5500...YELLOW IS MISSING

I had a defective primary transfer unit. I put the old unit back in and it worked fine. Had to reorder a different unit from Sharp and it's running like a top now.